Overnight Visits Research Articles

The extent of overtourism in some European locations using multi-criteria decision-making methods between 2014 and 2023

Purpose Overtourism has been identified as a significant global problem with numbers of negative externalities. The purpose of this paper is to contribute to the establishment of a standard that objectively measures the extent of tourism to produce a dynamic ranking of selected European settlements, as there is a lack of studies using sophisticated statistical methods to analyse secondary data on overtourism. Design/methodology/approach The 28 selected sites, studied according to their involvement in overtourism, were ranked using multi-criteria decision-Mmaking Methods between 2014 and 2023. Rankings were calculated by VIKOR, TOPSIS and MMOORA, and an aggregate ranking was created by using the cross-entropy optimization. Additionally, the annual changes in the rankings were presented graphically using principal component analysis on a two-dimensional space, referred to as the “sites' space.” Finally, the sites were clustered into three distinct groups based on their level of overtourism: less, medium and more. This was achieved through the use of the K-means algorithm. Findings Following the onset of the pandemic in 2020, there was a notable decline in overtourism. However, following the year 2021, the numbers began to rise once more, and by 2022, they had returned to their pre-pandemic levels. Among the methods, MMOORA demonstrated the most effective performance in comparison to the optimal ranking. Originality/value The applied methods with novel rank aggregation could also shed light on the most relevant indicators to overtourism. These included the number of nights spent in paid accommodation per population, the number of overnight visits per population and the number of air passengers.

An exploratory pilot study on social rhythm regularity, and its associations with sleep, circadian, affective, and alcohol use outcomes in late adolescents.

The current exploratory pilot study examined whether social rhythm regularity, as measured by a social rhythm metric, was associated with: (1) the regularity of circadian rhythms and/or sleep regularity metrics; and (2) sleep quality, affective function and alcohol use. Late adolescents (18-22 years old) who drink alcohol (n = 36; 61.1% female, Mage = 21.26 years) completed a 14-day ecological momentary assessment protocol, wore a wrist actigraph for 14 days, and completed two overnight visits (Thursday and Sunday) to assess dim light melatonin onset. Sleep regularity metrics included standard deviation, composite phase deviation, social jet lag and inter-daily stability. We used dim light melatonin onset data to calculate the stability of the circadian phase (Sunday minus Thursday). Participants completed surveys and ecological momentary assessments that assessed global and daily sleep quality, affective function, and alcohol use. Correlational analysis and robust regression modelling were used. More regular social rhythms were associated with higher regularities of mid-sleep timing based on standard deviations, but were not associated with other sleep regularity metrics or stability of the circadian phase. More regular social rhythms were associated with better sleep quality, but were not associated with affective function or alcohol use. Social rhythm regularity is a unique construct compared with existing sleep quality metrics. In contrast with the social zeitgeber hypothesis, social rhythm regularity was not associated with circadian rhythm regularity measured by dim light melatonin onset. However, social rhythm regularity may be an under-recognized contributor to better sleep quality.

0066 Continuous Theta Burst Transcranial Magnetic Stimulation for Insomnia and its Effects on Verbal Recall Performance

Abstract Introduction In this project, we studied the efficacy of focused inhibitory stimulation using continuous theta burst stimulation (cTBS) repetitive transcranial magnetic stimulation (rTMS) on an easily accessible region of the default mode network (DMN). As reported elsewhere, we found that cTBS improved brain connectivity and objectively measured sleep. However, there is little known about the side effects of rTMS in the treatment of insomnia, so here we evaluated the effects on verbal memory recall. Methods Twenty adults with clinical insomnia completed this study (Mage=26.90, SD=6.56). Participants conducted two overnight visits during the study; one where they received active cTBS and one where they received a sham cTBS prior to sleep. Participants completed the California Verbal Learning Test (CVLT) before stimulation and again completed the recall portion following a night of laboratory monitored sleep. We analyzed CVLT recall performance with a repeated measures ANOVA with factors of condition (active cTBS vs. sham cTBS) and session (Short Recall, Long Recall, Cued Recall, and Recognition). Results Contrary to our hypothesis, our analyses indicate there was no significant effects on recall performance due to active cTBS. There was no main effect of condition on recall scores post-TMS administration (F(1, 18)=1.162, p=.220, ηp2 = 0.082). There was no interaction effect of active or sham cTBS on recall performance (F(4, 15)=.828, p=.528, ηp2=0.181). Posthoc pairwise comparisons demonstrated that there was no significant difference post-TMS administration between active cTBS and sham cTBS conditions on long recall, cued recall, or recognition (p>.05). There was no significant difference post-TMS administration on short-term recall performance. Participants scored lower on short term recall after receiving active cTBS (M=12.632; SD=2.910) than after sham cTBS administration (M=13.42 ;SD=2.545) (p=.048). Conclusion Compared to sham, active cTBS was not associated with any significant difference in long-term recall performance after TMS administration. While the results demonstrate there are short term effects to recall after administration, recall scores bounce back shortly after. While participants didn’t necessarily improve with active cTBS, it is beneficial to know there are no long-term harmful effects of active cTBS on recall as side effect of insomnia treatment. Support (if any) W81XWH2010173

Spring Snowpack Influences on the Volume and Timing of Spring and Peak-Season Overnight Visitation to Yosemite Wilderness

Abstract Wilderness visitation, particularly overnight use, is reactive to climate variability because backpackers face greater exposure to and dependence on environmental conditions. This study examines the effect that spring snowpack had on the timing and volume of permits issued for overnight use of the Yosemite Wilderness during peak and shoulder-season months (April–October) from 2002 to 2019. We categorize 1 April snowpack at Tuolumne Meadows into snow drought (<75%), high snowpack (>125%), and near-average snowpack (75%–125%). Results confirm wilderness-wide differences between snowpack categories, including change in spring overnight visitors (April–June: +20% snow drought and −28% high snowpack). Our findings confirm that snow drought allows for more access to high-elevation trailheads when seasonal roads are open earlier in spring (May–June: +74% Tioga Road and +81% Tuolumne Meadows). Mid- to high-elevation trailheads experience a sustained increase in use during high-snowpack years (June–October: +12% Yosemite Valley and Big Oak Flat; +15% Glacier Point Road and Wawona; +32% Hetch Hetchy) because a narrower seasonal access window leads to filled permit quotas in the high country and displaces use to lower-elevation trailheads. These findings have implications for wilderness stewards, including biophysical and experiential impacts on wilderness character from earlier and longer seasons, especially at higher elevation and in fragile alpine and subalpine areas, as snow drought in mountain-protected areas becomes more common. Recommendations to address greater early-season use and its attendant impacts include adaptively managing permits for different types of snowpack years, including potential changes in the number, timing, and destination of select trailhead quotas.

Topical Potassium Channel Blockage Improves Pharyngeal Collapsibility: A Translational, Placebo-Controlled Trial

Potassium (K+) channel inhibition has been identified in animal models as a potential target to increase pharyngeal dilator muscle activity and to treat OSA. However, these findings have not yet been translated to humans. Does a novel, potent, tandem of P domains in a weak inward rectifying K+ channel (TWIK)-related acid-sensitive K+ (TASK) 1/3 channel antagonist, BAY2586116, improve pharyngeal collapsibility in pigs and humans, and secondarily, what is the optimal dose and method of topical application? In the preclinical study, pharyngeal muscle activity and upper-airway collapsibility via transient negative pressure application was quantified in 13 anesthetized pigs during administration of placebo, 0.3 μg, 3 μg, and 30 μg nasal drops of BAY2586116. In the clinical study, 12 people with OSA instrumented with polysomnography equipment, an epiglottic pressure catheter, pneumotachograph, and nasal mask to monitor sleep and breathing performed up to four detailed upper airway sleep physiology studies. Participants received BAY2586116 (160 μg) or placebo nasal spray before sleep via a double-masked, randomized, crossover design. Most participants also returned for three additional overnight visits: (1) nasal drops (160 μg), (2) half-dose nasal spray (80 μg), and (3) direct endoscopic application (160 μg). The upper-airway critical closing pressure (Pcrit) during sleep was quantified at each visit. Consistent and sustained improvements in pharyngeal collapsibility to negative pressure were found with 3 and 30 μg of BAY2586116 vsplacebo in pigs. Similarly, BAY2586116 improved pharyngeal collapsibility by an average of approximately 2cm H2O vsplacebo, regardless of topical application method and dose (P< .008, mixed model) in participants with OSA. Acute topical application of BAY2586116 improves upper-airway collapsibility in anesthetized pigs and sleeping humans with OSA. These novel physiologic findings highlight the therapeutic potential to target potassium channel mechanisms to treat OSA. ClinicalTrials.gov; No.: NCT04236440; URL: www. gov.

Featured Collection Introduction: Severe Sustained Drought Revisited: Managing the Colorado River System in Times of Water Shortage 25 Years Later — Part I

Featured Collection Introduction: Severe Sustained Drought Revisited: Managing the Colorado River System in Times of Water Shortage 25 Years Later — Part I

0658 Slow-Wave Sleep Disruption Decreases Ability to Recognize Certain Negative Emotions

Abstract Introduction Research has demonstrated that sleep deprivation may alter emotion recognition. Given that emotion recognition is critical for effective human communication, it is essential to understand how sleep is involved in this process. Slow-wave sleep (SWS) has been suggested to be important for the consolidation and processing of emotional memories and neuroplasticity. This study aimed to examine the impact of experimental disruption of SWS on emotion recognition to further understand the contribution of SWS. Methods 31 participants (20 individuals diagnosed with Major Depressive Disorder (MDD), 11 healthy controls (HC)) completed two overnight sleep studies spaced one week apart. One night served as baseline (BL) and on the other night participants underwent slow-wave disruption (SWD), where SWS was disrupted using auditory stimulation. In the morning following each overnight visit, participants completed an emotion recognition task. Accuracy scores were computed as the percentage correct in each of 10 categories of emotions (anger, contempt, disgust, embarrassment, fear, joy, neutral, pride, sadness, and surprise). Repeated measures ANOVA was used to assess the impact of SWD on emotion recognition with group (HC, MDD) as the between subjects factor and condition (BL, SWD) as the within subjects factor. Results Results revealed a significant main effect of condition for disgust (F=13.72, p&amp;lt; .001), embarrassment (F=6.23, p=.019), and surprise (F=8.06, p=.008), with follow-up t-tests demonstrating that accuracy for the recognition of disgust and embarrassment decreased following SWD and accuracy for surprise increasing following SWD. No significant interactions were found for group*condition (ps&amp;gt;.105). Conclusion These results suggest that while SWD decreases the ability to recognize certain negative emotions, it also increases the ability to recognize surprise, which is in line with previous research examining acute total sleep deprivation. Interestingly, there appears to be no difference in the ability to recognize emotions between individuals with and without depression. Slow-wave sleep deficits, common in disorders such as depression and schizophrenia, may therefore contribute to poor communication abilities through decreased ability to recognize emotions, increasing the risk of interpersonal distress and mental health problems. Support (If Any) Goldschmied: K23MH118580 (NIMH)

0263 Slow-wave Disruption Improves Irritability in Males with Major Depression: Potential Implications for Understanding the Impact of Sex Differences on Sleep and Neuroplasticity

Abstract Introduction Irritability has been proposed to be a core symptom of male-specific major depressive disorder (MDD), with a greater propensity to experiencing anger attacks and overreacting to minor annoyances compared to females with MDD. Males with MDD have also been shown to exhibit a pattern of reduced slow-wave sleep (SWS) that is not characteristic of females. Because SWS has been implicated in the homeostatic regulation of neuroplasticity, it is possible that this mood dysfunction in males is a result of SWS alterations via impairments in neuroplasticity. Therefore, in this study we aimed to manipulate SWS and examine its impact on mood. Methods 19 individuals (11 F) with MDD were recruited for an ongoing clinical trial. Participants spent two nights in the sleep laboratory one week apart: a baseline (BL) night, and a night of slow-wave sleep disruption (SWD) utilizing auditory stimulation. Irritability was assessed in the morning following each overnight visit using the 5-item Brief Irritability Test (BITe). Repeated measures ANOVA was used to evaluate the change in irritability following SWD with condition (BL, SWD) as the within-subject factor and sex (M, F) as the between-subjects factor. Results Results revealed a significant Condition x Sex interaction (F(1,17) =10.1, p=.006) for change in irritability scores, with post-hoc t-tests indicating that males with MDD showed a significant decrease in irritability following SWD, t(7)=2.22, p&amp;lt;.05 while women showed a significant increase in irritability, t(10)=-2.34, p&amp;lt;.05. Changes in irritability were not found to be associated with changes in N3. Conclusion These data demonstrate that experimentally reducing SWS decreases irritability, a core symptom of mood dysfunction, in males with MDD. As SWS has been theorized to facilitate synaptic downscaling, these results may indicate that maintaining waking levels of synaptic strength in males improves depressive symptomatology and may point to the importance of sex differences in sleep and psychopathology. Moreover, these results suggest that the modulation of neuroplasticity via sleep manipulation may be a potential therapeutic target. Support (If Any) K23MH118580 (JG)

The Current Landscape of Congenital Heart Surgery in Northern China: A Geographic and Population-Based Analysis.

Background: Congenital heart disease (CHD) is the leading birth defect in China, and many patients require congenital heart surgery (CHS) to achieve optimal outcomes. However, the current landscape and population accessibility to specialist resources for CHS in China are unclear.Methods: Care facilities performing CHS were identified from the 2018 white book of Chinese cardiovascular surgery and were categorized as full or limited facilities based on specialist capacity. Census-based population data and road data were obtained from administrative sources. Service area analysis of all facilities was performed to estimate geographic accessibility.Results: Of 93 facilities in 14 provinces and municipalities in northern China, only 30.1% had full specialist capacity. The shortage of pediatric cardiologists and mechanical circulatory support was the primary limiting factor. In 2018, 61.3% of facilities performed <200 CHS cases, and 31.6% of all CHS cases (N = 30,921) were performed in limited facilities with substantially lower volume than full-capacity facilities (median value: 85.0 vs. 368.0). Beijing had a disproportionately higher CHS volume (367 cases per million population) than other provinces. Of all children under 5 in northern China, only 12.9% live within 30 km (a typical half-day visit) of the service areas of all facilities. Compared to children from the eastern region (31.4%), 71.8% of children from the central region and 70.2% of children from the western region needed to travel >180 km (a typical overnight visit) to receive care in full-capacity facilities.Conclusions: Many facilities for CHS in northern China had limited specialist capacity, and many CHD patients received suboptimal surgical care. Policy measures should address the significant geographic disparities to receive high-quality surgical care among disadvantaged patients.

854 Sexsomnia in a Divorce Proceeding and its Custody Implications

Abstract Introduction Sexsomnia is a NREM parasomnia under the subtype of Confusional Arousals, defined as abnormal sexual behaviors emerging from partial arousals during slow-wave sleep. Case reports suggest that is more common in men. Precipitating factors include Obstructive Sleep Apnea, insufficient sleep, alcohol and fatigue/stress and history of NREM parasomnias. Report of case(s) A 37-year-old male with bruxism (using mouth guard) and anxiety for 7 years, who presented to the sleep clinic for a second opinion to discuss concerns around the safety of his children due to his sleep related sexual behavior. Sexsomnia was first noted with the stressors related to becoming a parent (fostering children and having biological children). Sexual behavior reported by the couple was mostly provoked with spouse’s touch during sleep. Behaviors ranging from fondling to aggressive sexual intercourse were reported to occur 1 to 3 times/week. There were no injuries during episodes which only occurred in the bedroom with the spouse and the patient was amnestic of his behavior. Due to marital discord provoked by other stressors, he began to sleep alone in the basement. A video-polysomnogram revealed no parasomnia, sleep apnea, or other sleep arousal disorders. Normal REM with atonia was observed. The patient was treated with Duloxetine 20mg for anxiety after the initial sleep visit. His condition contributed to marital separation. In the divorce proceedings, the spouse argued for denial of visitation rights related to his sleep-sexual behaviors noting that the children may be at risk. After separation, his anxiety and stress levels lowered in conjunction with therapy and medication. Follow up after 2 months found the patient asymptomatic. He placed an alarm on his bedroom door, to alert him and others during sleep. There are no published reports to provide a prediction as to whether his condition would-be supporting restrictions in overnight visitation by the foster and biological children. Conclusion In this case, there was a precedent condition (bruxism) and precipitating stress and anxiety, known to provoke NREM parasomnia. The absence of polysomnographic evidence is not unusual. Forensic repercussions, in particular prospective calculations of risk, are poorly described in the literature. Support (if any):

Wikipedia matters

AbstractWe document a causal impact of online user‐generated information on real‐world economic outcomes. In particular, we conduct a randomized field experiment to test whether additional content on Wikipedia pages about cities affects tourists' choices of overnight visits. Our treatment of adding information to Wikipedia increases overnight stays in treated cities compared to nontreated cities. The impact is largely driven by improvements to shorter and relatively incomplete pages on Wikipedia. Our findings highlight the value of digital public goods for informing individual choices.

0175 Light Improves Alertness and Mood During the Sleep Inertia Period Following Slow Wave Sleep

Abstract Introduction Waking from sleep, especially slow wave sleep (SWS), is associated with reduced alertness known as sleep inertia. Light improves alertness during sleep deprivation and circadian misalignment. In this study, we assessed the efficacy of light to improve alertness and mood immediately after waking from SWS. Methods Twelve participants kept a sleep schedule of 8.5 h for 5 nights and 5 h for one night prior to the overnight laboratory visit (confirmed by actigraphy). Participants went to bed at their scheduled habitual bedtime in the laboratory and were monitored by standard polysomnography. After at least 5 min of SWS, participants were awoken and exposed to either red ambient light (control) or blue-enriched bright light (light) for 1 h. During this time, participants completed a subjective scale of alertness (Karolinska Sleepiness Scale, KSS) and visual analogue scales (VAS) of mood at 2 min, 17 min, 32 min, and 47 min after waking. Following this sleep inertia measurement period, all lights were turned off and participants were allowed to return to sleep. They were then awoken again from their subsequent SWS period and exposed to the opposite condition (control or light). A linear mixed-effects model with fixed effects of condition, time, and condition*time and a random effect of participant was used to determine the impact of light across the testing period. An average of baseline responses (pre-sleep) was included as a covariate. Results Compared to the control condition, participants exposed to blue-enriched bright light reported feeling more alert (KSS: F1,77=4.955, p=.029; VASalert: F1,77=8.226, p=.005), more cheerful (VAScheerful: F1,77=8.615, p=.004), less depressed (VASdepressed: F1,77=4.649, p=.034), and less lethargic (VASlethargic: F1,77=5.652, p=.020). Conclusion Exposure to blue-enriched bright light immediately after waking from SWS may help to improve subjective alertness and mood. Future analyses will explore whether these findings extend to effects on cognitive performance. Support Naval Postgraduate School Grant. NASA Airspace Operations and Safety Program, System-Wide Safety Project.

0078 Influence of Light on Brain Activity Upon Waking From Slow Wave Sleep

Abstract Introduction Waking from sleep is associated with reduced alertness due to sleep inertia. Light acutely improves alertness during sleep deprivation. In this study we assessed the influence of light on brain activity and connectivity after waking from slow wave sleep (SWS). Methods Twelve participants kept an actigraphy-confirmed stable sleep schedule with 8.5 hours for five nights and five hours for one night prior to an overnight laboratory visit. Participants completed two three-minute Karolinska Drowsiness Tests (KDT) before going to bed at their habitual bedtime. They were monitored continuously using high-density EEG (32-channel; Brain Products GmbH). Participants were woken twice and exposed to red light (0.01 melanopic-lux; control) or blue-enriched light (63.62 melanopic-lux) for one hour, in a randomized order, following at least five minutes of SWS. EEG artifact were removed algorithmically and the spectral composition of each electrode (i.e., fast fourier transform, FFT) and effective connectivity (i.e., partial directed coherence, PDC) between each electrode were estimated. A graphical analysis was conducted to extract features relevant to the facilitation of efficient communication between electrodes. All data were averaged within frequency bins of interest that correspond to delta (1-3Hz), theta (4-7Hz), alpha (8-12Hz), and beta (13-25Hz) bands and expressed relative to the pre-sleep baseline. Results Compared to the pre-sleep baseline, participants exposed to blue-enriched light experienced reduced theta and alpha activity; however, these results were not significantly different from the control. In contrast, the communication of frontal electrodes significantly increased across all frequency bands compared to the control, and this effect was most prominent in the alpha (t(11)=3.80, p=.005) and beta bands (t(11)=3.92, p=.004). Conclusion Exposure to blue-enriched light immediately after waking from SWS may accelerate the process of waking and help to improve alertness by facilitating communication between brain regions. Future analyses will explore the temporal persistence and granularity of the communicative properties associated with this response. Support Naval Postgraduate School Grant. NASA Airspace Operations and Safety Program, System-Wide Safety Project.

The Effect of Food on the Pharmacokinetics of Sildenafil after Single Administration of a Sublingual Testosterone and Oral Sildenafil Combination Tablet in Healthy Female Subjects

IntroductionFemale sexual interest/arousal disorder (FSIAD) affects many women worldwide, but pharmacological treatment options are scarce. A new medicine being developed for FSIAD is an on-demand, dual-route, dual-release drug combination product containing 0.5 mg testosterone (T) and 50 mg sildenafil (S), referred to here as T+S. AimThe aim of this study was to compare the effect of a fed and a fasted state on the pharmacokinetics of sildenafil following administration of T+S. MethodsEighteen healthy women were administered T+S under fed and fasted conditions during 2 separate overnight visits in this randomized, open-label, balanced, 2-period, 2-treatment, 2-sequence crossover study. Main Outcome MeasuresThe pharmacokinetics of sildenafil and its active metabolite N-desmethyl sildenafil were determined over a 24-hour period. Total testosterone was assessed only at a limited number of time points for quality purposes, as sublingual uptake is not expected to be affected by food intake. ResultsThe observed geometric mean ratios (GMRs) and 90% confidence intervals of sildenafil were not all contained within the prespecified bounds (0.80, 1.25). The GMR (90% CI) for plasma AUC0–last was 1.2753 (0.9706–1.6755); for AUC0–14h, it was 1.7521 (1.0819–2.8374); and for Cmax, it was 1.5591 (0.8634–2.8153). Only lower limits of the CIs fell within the bounds. For N-desmethyl sildenafil, the GMR (90% CI) for AUC0–last was 0.8437 (0.6738–1.0564); for AUC0–10h, it was 1.0847 (0.7648–1.5383); and for Cmax, it was 1.0083 (0.6638–1.5318). Only the GMRs were contained within bounds. No differences were observed between plasma testosterone Cmax and Tmax under fed and fasted conditions, which is in line with expectations for a sublingual administration. Clinical ImplicationsThe T+S combination tablet ruptures too late when taken in a fasted state and should therefore not be taken on an empty stomach. Strengths & LimitationsThis is a well-controlled study that provides important insights into the performance characteristics of the delayed-release coating of the combination tablet. The higher variability of the pharmacokinetic parameters in the fasted state was caused by severely delayed rupture in one-third of the women. A reason for this is proposed but the present data do not explain this phenomenon. ConclusionThe pharmacokinetics of sildenafil from this modified-release tablet are more robust under fed conditions as compared to the artificial fasted condition where no food is consumed 10 hours prior to and 4 hours after dosing. The dosing situation under the tested fasting condition does not represent the expected common use of this product. Patients should, however, be instructed not to take the tablet on an empty stomach.Bloemers J, Gerritsen J, van Rooij K, et al. The Effect of Food on the Pharmacokinetics of Sildenafil After Single Administration of a Sublingual Testosterone and Oral Sildenafil Combination Tablet in Healthy Female Subjects. J Sex Med 2019; 19:1433–1443.

Influence of Short-Term Orthokeratology to Corneal Tangent Modulus: A Randomized Study

ABSTRACTPurpose: Influence of orthokeratology on corneal biomechanics is equivocal using Ocular Response Analyzer, ORA. Implementing indentation method, corneal tangent modulus was measured and monitored in short-term orthokeratology.Materials and Methods: Sixteen young subjects with refractive errors between –4D to –5D sphere and astigmatism within –1.50D were recruited. One randomly selected eye wore orthokeratology lens (treatment), and the fellow eye wore conventional rigid gas permeable lens (control). Lenses were worn for 30 and 60 minutes and one night separately with a week of washout period in between. The first two visits were randomly scheduled and before the overnight visit. Eyes were kept closed during all the lens wearing periods. Corneal radius, thickness, and biomechanics (using both ORA and an indentation device) were compared between eyes prior to each visit, and then before and after lens wear. Associations between baseline corneal biomechanics and central cornea from overnight visit were investigated.Results: Corneal parameters were similar in each visit before lens wear. Significant corneal flattening was observed in treatment eyes, and flattening increased with wearing time. Control eyes showed no significant corneal curvature changes. Corneal resistance factor (CRF) reduced by 0.42mmHg (± 0.68mmHg) after 30 minutes of orthokeratology treatment. Corneal hysteresis (CH) reduced by 0.42mmHg (+/- 0.63mmHg) in control eyes from overnight wear. Both eyes showed stable tangent modulus, E, throughout the study. A lower CH (r = 0.51, p = 0.046) and a higher E (r = 0.53, p = 0.037) at baseline was significantly associated with greater corneal flattening along the flattest meridian in treatment eyes.Conclusions: Short‐term orthokeratology had no significant effect on corneal tangent modulus. Changes in CH and CRF could be related to their intrinsic measurement variability. Corneal tangent modulus provided another measure of corneal biomechanics. Long-term study is required to investigate predictive role of corneal biomechanics in orthokeratology.

A multi-level spatial analysis of clinical malaria and subclinical Plasmodium infections in Pailin Province, Cambodia

BackgroundThe malaria burden is decreasing throughout the Greater Mekong Subregion, however transmission persists in some areas. Human movement, subclinical infections and complicated transmission patterns contribute to the persistence of malaria. This research describes the micro-geographical epidemiology of both clinical malaria and subclinical Plasmodium infections in three villages in Western Cambodia. MethodsThree villages in Western Cambodia were selected for the study based on high reported Plasmodium falciparum incidence. A census was conducted at the beginning of the study, including demographic information and travel history. The total population was 1766. Cross-sectional surveys were conducted every three months from June 2013 to June 2014. Plasmodium infections were detected using an ultra-sensitive, high-volume, quantitative polymerase chain reaction (uPCR) technique. Clinical episodes were recorded by village health workers. The geographic coordinates (latitude and longitude) were collected for all houses and all participants were linked to their respective houses using a demographic surveillance system. Written informed consent was obtained from all participants. ResultsMost clinical episodes and subclinical infections occurred within a single study village. Clinical Plasmodium vivax episodes clustered spatially in each village but only lasted for a month. In one study village subclinical infections clustered in geographic proximity to clusters of clinical episodes. The largest risk factor for clinical P. falciparum episodes was living in a house where another clinical P. falciparum episode occurred (model adjusted odds ratio (AOR): 6.9; CI: 2.3–19. 8). Subclinical infections of both P. vivax and P. falciparum were associated with clinical episodes of the same species (AOR: 5.8; CI: 1.5–19.7 for P. falciparum and AOR: 14.6; CI: 8.6–25.2 for P. vivax) and self-reported overnight visits to forested areas (AOR = 3.8; CI: 1.8–7. 7 for P. falciparum and AOR = 2.9; CI: 1.7–4.8 for P. vivax). DiscussionSpatial clustering within the villages was transient, making the prediction of spatial clusters difficult. Interventions that are dependent on predicting spatial clusters (such as reactive case detection) would only have detected a small proportion of cases unless the entire village was screened within a limited time frame and with a highly sensitive diagnostic test. Subclinical infections may be acquired outside of the village (particularly in forested areas) and may play an important role in transmission.

Abstract P360: 24-hour Blood Pressure Profiles Associated With Sleep Duration

Introduction: Insufficient sleep is associated incident hypertension. Because blood pressure (BP) varies across 24h, shorter sleep may be associated with increased BP across all 24h. Additionally, we evaluated whether BP variability was also associated with shorter sleep. Methods: Participants were adults with untreated prehypertension or stage-1 hypertension assessed at baseline as part of a clinical trial. Recordings took place during overnight visits in a Clinical Research Center. Sleep was reported by nurses continuously monitoring patients. Those with &lt;7h sleep were classified “shorter” (N=13) and the rest “longer” (N=30). BP was assessed with a Spacelabs ambulatory monitor. Linear regression models evaluated effect of group on day, night, and 24h systolic and diastolic BP and heart rate (HR). Results: The “shorter” group slept for M=370 (SD=87) minutes and the “longer” group slept for M=521 (SD=51) mins. Results for day, night, and 24h systolic and diastolic blood pressure and heart rate are reported in the Table. Also, higher 24h variability in systolic BP (B=1.2, p=0.03), diastolic BP (B=1.4, p=0.002), and HR (B=1.3, p=0.03) were demonstrated. This was reflected in higher variability during daytime for systolic BP (B=1.1, p=0.04), diastolic BP (B=1.5, p=0.001), and HR (B=1.2, p=0.05); no differences in variability were seen during the night. Conclusions: Shorter sleep duration is associated with higher systolic BP and HR across 24h (day and night), as well as increased variability in systolic and diastolic BP and HR across 24h (during the day in particular). This could provide additional insight in to how sleep duration is associated with hypertension incidence.

A novel clinical approach to evaluating changes in fat oxidation in healthy, overnight-fasted subjects

Obesity is characterized by impaired fat oxidation, and, therefore, the development of therapeutics designed to enhance fat oxidation for treating obesity is a growing focus in drug discovery. Evaluating such agents, however, is challenging in a clinical setting; requisite overnight fasting prior to a study visit increases whole body fat oxidation in lean, healthy subjects, making incremental increases potentially difficult to detect. We recruited 16 lean/overweight participants and eight obese participants to evaluate novel methodology designed to optimally detect increases in fat oxidation. Carbohydrate intake was increased for three days leading up to the overnight test visit and evaluated as either a standalone strategy to suppress overnight fasting-related increases in fat oxidation or was combined with overnight administration of IV glucose in a subset of lean/overweight subjects. Indirect calorimetry was performed the following morning to examine the degree to which these interventions were able to diminish fasting related increases in fat oxidation. Fat oxidation was then subsequently stimulated by challenging patients with a lipid infusion to determine the importance of the preceding interventions on the ability to detect statistically significant increases in fat oxidation. In lean/overweight subjects, suppression of fasting-related increases in fat oxidation via increased dietary carbohydrate intake was not necessary to detect subsequent meaningful increases in fat oxidation rates following Intralipid infusion; however, a statistically significant decrease in respiratory quotient following Intralipid infusion could only be observed when the infusion was preceded with high carbohydrate dietary intake. Glucose infusion, which further suppressed fasting-related fat oxidation, in turn led to more dramatic increases in Intralipid-driven fat oxidation. Both lean/overweight and obese subjects could demonstrate statistically significant increases in fat oxidation following Intralipid infusion, a finding which supports the inclusion of obese subjects in similar future clinical studies. Lastly, serum levels of β-hydroxybutyrate correlated strongly with fat oxidation rates, as well as respiratory quotient, suggesting potential as a surrogate biomarker of fax oxidation. Taken together, we demonstrate the utility of novel methodology to facilitate measuring changes in fat oxidation in lean/overweight and obese human volunteers in a clinical setting similar to that needed to test drugs designed to increase fat oxidation.

Patient perceptions of patient-centred care: empirical test of a theoretical model.

Patient perception measures are gaining increasing interest among scholars and practitioners. The aim of this study was to empirically examine a conceptual model of patient-centred care using patient perception survey data. Patient-centred care is one of the Institute of Medicine's objectives for improving health care in the 21st century. Patient interviews conducted by the Picker Institute/Commonwealth Fund in the 1980s resulted in a theoretical model and survey questions with dimensions and attributes patients defined as patient-centered. The present study used survey data from patients with overnight visits at 142 U.S. hospitals. Regression analysis found significant support for the theoretical model. Perceptions of emotional support had the strongest relationship with overall care ratings. Coordination of care, and physical comfort were strongly related as well. Understanding how patients experience their care can help improve understanding of what patients believe is patient-centred, and of how care processes relate to important patient outcomes.

YOUNG CHILDREN, ATTACHMENT SECURITY, AND PARENTING SCHEDULES

The focus of a recent Family Court Review Special Issue on attachment, separation, and divorce included perspectives primarily from researchers in the Bowlby/Ainsworth tradition. A number of the authors made recommendations against overnight visits for very young children. I review conceptualizations and measures of attachment security as well as empirical findings. Currently the foundation to make general recommendations regarding overnight visits is inadequate. Caution is needed in using attachment measures in court evaluations and regarding restrictive legal presumptions and theoretical orientations. Custody and access evaluations and decisions need to apply scientifically sound principles to the individual characteristics of each case.Key Points for the Family Court Community: Simple “yes” or “no” answers are inadequate regarding the question of overnight visits for young children. Attachment security can change and is influenced by multiple factors over the life span. There are important scientific, ethical, and cost factors when considering the possible use of attachment security measures in custody evaluation. Scientific findings about how overnight visits affect young children are mixed and seem best explained by differences in parental characteristics and interactions. Each case deserves decision‐making based on careful reasoning, informed by scientific findings and the relevant individual circumstances.